1. Field of the Invention
The present invention relates to methods for preparing a dough and/or baked product with a lactonohydrolase.
2. Description of the Related Art
The strength of a dough is an important aspect of baking for both small-scale and large-scale applications. A strong dough has a greater tolerance for mixing time, proofing time, and mechanical vibrations during dough transport, whereas a weak dough is less tolerant to these treatments. A strong dough with superior rheological and handling properties results from flour containing a strong gluten network. Flour with a low protein content or a poor gluten quality results in a weak dough.
Dough xe2x80x9cconditionersxe2x80x9d are well known in the baking industry. The addition of conditioners to bread dough has resulted in improved machinability of the dough and improved texture, volume, flavor, and freshness (anti-staling) of the bread. Nonspecific oxidants, such as iodates, peroxides, ascorbic acid, potassium bromate and azodicarbonamide have a gluten strengthening effect. It has been suggested that these conditioners induce the formation of interprotein bonds which strengthen the gluten, and thereby the dough. However, the use of several of the currently available chemical oxidizing agents has been met with consumer resistance or is not permitted by regulatory agencies.
The use of enzymes as dough conditioners has been considered as an alternative to the chemical conditioners. A number of enzymes have been used recently as dough and/or bread improving agents, in particular, enzymes that act on components present in large amounts in the dough. Examples of such enzymes are found within the groups of amylases, proteases, glucose oxidases, and (hemi)cellulases, including pentosanases.
Lactonohydrolases reversibly catalyze the hydrolysis of lactone compounds to hydroxy acids, i.e., they mediate the interconversion between the lactone and acid forms of hydroxy carboxylic acids.
Shimizu et al. (1992, European Journal of Biochemistry 209: 383-390) have disclosed a lactonohydrolase obtained from Fusarium oxysporum. This enzyme preparation stereospecifically hydrolyzes aldonate lactones such as D-galactono-xcex3-lactone and D-glucono-xcex4-lactone. In addition, the Fusarium oxysporum lactonohydrolase catalyzes the asymmetric hydrolysis of D-pantoyl lactone, which can be used as a chiral building block for the synthesis of D-pantothenate (Shimazu and Kataoka, 1996, Annals of the New York Academy of Sciences 799:650-658; Kataoka et al., 1995, Appl. Microbiol. Biotechnol. 44: 333-338; Kataoka et al., 1996, Enzyme Microb. Technol. 19: 307-310). Furthermore, lactonohydrolase irreversibly hydrolyzes a number of aromatic lactones, such as dihydrocoumarin and homogentisic-acid lactone.
The cloning and expression of a Fusarium oxysporum lactonohydrolase gene has been disclosed (WO 97/10341).
It is the object of the present invention to improve the properties of dough and/or baked products by the use of a lactonohydrolase.
The present invention relates to methods for preparing a dough, comprising incorporating into the dough an effective amount of one or more lactonohydrolases.
The present invention also relates to methods for preparing a baked product.
The present invention also relates to compositions comprising an effective amount of one or more lactonohydrolases, for improving one or more properties of a dough and/or a baked product obtained from the dough, and a carrier and/or a baking ingredient.
The present invention also relates to doughs or baked products.
The present invention further relates to pre-mixes for a dough comprising an effective amount of one or more lactonohydrolases, for improving one or more properties of a dough and/or a baked product obtained from the dough, and a carrier and/or a baking ingredient.